Allow excluding checkers from ament_lint_auto_find_test_dependencies about ament_lint

[dirk-thomas]

I don't think the proposed approach:

Adding and EXCLUDE option in ament_lint_auto_find_test_dependencies could make the code above cleaner: e.g.

would work. The ament_lint_auto extension point is being triggered when ament_package() is called and if that call happens after the above snippet it would still trigger all linters previous being found (independently from how they are found - by ament_lint_auto_find_test_dependencies or an explicit call to find_package).

If this feature were implemented, would it be accepted?

Sure.

[jpsamper2009]

@dirk-thomas Thanks for the quick response!

Re:

The ament_lint_auto extension point is being triggered when ament_package() is called and if that call happens after the above snippet it would still trigger all linters previous being found (independently from how they are found - by ament_lint_auto_find_test_dependencies or an explicit call to find_package).

So we would need to find a way to determine if a package was found by ament_lint_auto_find_test_dependencies or by an explicit call, correct?

What if:

We set a variable in ament_lint_auto_find_test_dependencies called REGISTER_AUTO_LINT_EXTENSIONS, which would then be used in each linter package (ament_cmake_cpplint, etc) to conditionally register the auto lint extension: e.g.,

macro(ament_lint_auto_find_test_dependencies)
...
  set(REGISTER_AMENT_LINT_AUTO_EXTENSIONS TRUE)
  # try to find_package() all test dependencies
  foreach(_dep ${${PROJECT_NAME}_TEST_DEPENDS})
    find_package(${_dep} QUIET)
    if(${_dep}_FOUND)
      list(APPEND ${PROJECT_NAME}_FOUND_TEST_DEPENDS ${_dep})
    endif()
  endforeach()
  set(REGISTER_AMENT_LINT_AUTO_EXTENSIONS FALSE)
endmacro()

Then in, ament_cmake_cpplint:

if(REGISTER_AMENT_LINT_AUTO_EXTENSIONS)
  ament_register_extension("ament_lint_auto" "ament_cmake_cpplint"
    "ament_cmake_cpplint_lint_hook.cmake")
endif()

If a package is missing the if(), it will still get picked up by ament_lint_auto_find_test_dependencies, so we don't run the risk of accidentally turning off a checker.

Thoughts?

[dirk-thomas]

Please see my comments on the PR: #133.

[dirk-thomas]

Implemented in #133.